Machine for pressing poultry food and other plastic mixtures



July 2, 1935. H. ZWART 2,007,104 MACHINE FOR PRESS ING POULTRY FOOD AND OTHER PLASTIC MIXTURES Filed March 17, 1951 F lg. 1.

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Patented July 2, 1935 i UliillfiiD STA-TES- PATENT, orrice 2,007,104, MACHINE FOE rnsssma POULTRY FOOD AND OTHER PLASTIC MIXTURES Herman Zwart,.Amsterd'am, Netherlands .ApplicationMarch 17, 1931,

Serial No. 523365 In thev Netherlands March: 22, 1930 2 Claims.v (Cl. 10714) have filed an application in the Netherlands om the: 22nd March, 1930;

The: present invention relates to machines'for the pressing of poultry food and other plastic mixtures-into the form of grains or small blocksa Machines for this 'purpose are known in. which apre'ss' cylinder is "employed in which a; press screw works, which latter conveys the material of a perforated plate which serves as a closure forthe' cylind'er at the front.

The construction of the usual pressing screws and the distance between the front end of the screw and the perforated plate are such that these known machines necessitate very" considerable power for their operation and that with the same material the hardness of the grains is-always the same, whilst apart from this inasmuch as the material is pressed by the endof the screw always only through one part of the perforated plate, the screw is stressed on one side only, asa result of which considerable wearing of the bearings'takesplace. Machines of this are' known wherein, when the machine is out of operation, the axle of the screw is ad-- j-u'stable for compensating forany wear which may occur through the medium of an adjustable hearing; but it is not possible in suck-r constructi'ons toobtain any" desired exact adjustment or the distance between the" end 'of the screw and the perforated plate, duringthe working operation. w

It" is the principal object of the present invention to provide means whereby as a result of a particular novel construction of the press screw and a means for exactly adjusting the latter during the working operation, in the first .place the necessary power can be reduced to a minimum so that in the production of the same materials less work is necessary than in the case of the known machines and in the second place, by the adjustment, the hardness of the grains is varied owing to the fact that the material located between the perforated plate and the front end of the screw before the resistance of the holes in the plate has been overcome is pressed to a greater extent than when the distance is smaller so that with higher compression of the material grains of greater hardness are formed than is the case when the layer of material in front of the plate. is thinner and the degree of compression is lower. The thickness of the layer, i. e. the distance between the plate and the end of the screw has therefore to be capable of very accurate adjustment, in fact, of

adjustment within fractions of a millimetre.

Onenovel feature of the machine according to the invention resides in the fact that the press screw consists of two parts, the pitch of the screw thread being sub-divided over a certain length at the front end by a'second screwi thread or a; plurality of screw threads into equal parts; whilst the depth of all the threads is such that they extend up to the axle and the whole press screw is exactly adjustable to fractions of a millimetre to and fro in the direction of the axle by displacement of the rear journal during the operation of the machine.

From this it will be seen that, in consequence of the provision of two independent screw threads at the front end, two pressing parts of the plate diametrically displaced with regard to one another are located opposite to' one another, which two: parts press the material through the holes in the perforated plate so" that. the lateral pressures equalize one another whereby'the bearings are-subjected to considerably less wear.

A preferred. constructional form according to the invention is illustrated in the accompanying drawing, in which,

Fig. 1 is a longitudinal section. of the machine,

Fig; 2 is a section taken on line IIII of Fig. 1, and" Fig. 3 is a front view of the press cylinder without'the' perforated plate.

Referring to the drawing, the machine consists of a press cylinder l with an inlet opening 2 and a perforated press plate 3 arranged at the front of the press cylinder I. The press cylinder 1 is closed at the rear by means of a cover 4', the press plate 3 and also the cover 4 being providedwith central bores for the passage of the ends 5 and 6 of the axle of the press screw. As clearly shown in Fig. 3, the cylinder I is constructed in a manner which provides a plurality of axially extending triangular grooves I it along the inner surface thereof and these grooves Ia are bounded by surfaces lb which have triangular or ratchet-like cross-sections. Such surfaces may be formed on the cylinder in any suitable manner as by grooving the inner surface or by affixing an inner lining consisting 1 and 21 extends from the rear towards the front around the axle and on the front end of the axle a second screw thread 28 extending over a certain length thereof is provided which is arranged so as to sub-divide the pitch of the screw thread 21 into equal parts. It is also possible to provide a plurality of screw threads 28 on the front end of the axle which screw threads would likewise divide the pitch of the thread 21 into equal parts. The depth of the various screw threads is such as to extend up to the axle 25. Inasmuch as the front end of the press screw is provided with two or more screw threads, two or more screw parts 24 and 29 are formed at the end which press the material through the perforated plate 3, whereby uniform pressure is exerted on the screw.

The rear part ID of the axle 25 which passes through the cover 4 is provided with a packing ring 9.

The press screw is driven by means of apinion I I mounted at the rear end. The cover 4 is provided with a rearwardly directed threaded flange l2. With the thread of this flange a second threaded flange l3 provided on a sleeve l4 engages, the said sleeve being mounted loosely on the end 6 of the axle of the press screw by means of a sleeve 15. The internal diameter of the flange I3 is somewhat larger than the diameter of the end 6 of the axle so that an annular chamber [6 is formed within in which an axial pressure bearing I1 is arranged, the rings of which rest respectively against the rear surface of the part 10 and the front surface of the sleeve I4. The sleeve l4 carries a collar l8 provided with a worm gear I9 which co-operates with a worm 20, the axle 2| of which is arranged in fixed supports 22, 23 and is provided with a hand wheel 21'. The transmission ratio is of such magnitude that the axle of the press screw can be displaced during the operation of the machine to the extent of fractional parts of a millimetre in the longitudinal direction forwards or backwards over a length of about. 25 millimetres, the operation being effected by turning the hand wheel 21 whereby the sleeve I4 is rotated with respect to the end 6 of the axle of the press screw, and is displaced, in consequence of the screw connection with the cover 4, in the longitudinal direction.

It will, of course, be understood that the operation of the machine must be effected in such manner that the axial displacements of the press screw can take place without influencing the drive. It will also be understood that the device for the adjustment of the press screw in the longitudinal direction can be arranged in various manners, the principal condition being that the adjustment of the said press screw is a fine adjustment which may be effected during the operation of the machine.

I claim:

1. A machine for compressing poultry food and other plastic mixtures into granular and other suitable form, comprising in combination: a press cylinder; a perforated press plate closing the front end of said cylinder; a front bearing in said press plate; a rear bearing box at the rear end of saidcylinder; an axle arranged in said cylinder and journalled in said front bearing and said bearing box; a press screw having a deep cut single thread and a deep out multiple thread on said axle within said cylinder; means for rotating said axle and said press screw; fine adjustment means for moving said rear bearing box backwards and forwards axially during the operation of the machine, whereby the distance between said bearing box and said press plate can be adjusted accurately within fractions of a millimetre; and means associated with said bearing box and said axle for enabling said bearing box to carry said axle and said press screw with it in its backward and forward movements.

2. A machine for compressing poultry food and other plastic mixtures into granular and other suitable form, comprising in combination: a press cylinder; a perforated press plate closing the front end of said cylinder; a front bearing on said press plate; a rear bearing box attached by a screw connection to the rear end of said cylinder; an axle within said cylinder journalled in said front bearing and said rear bearing box; a press screw on said axle having a deep cut thread and having at its front part one or more deep cut threads superposed on the first named thread; means for rotating said axle and said press screw; a worm on the exterior of said bearing box; a worm wheel co-operating with said worm to turn said bearing box and thus move it axially backwards and forwards on its screw connection; means for operating said worm wheel and worm to move said bearing box axially and adjust its position relatively to said press plate within fractions of a millimetre during the operation of the machine; and means associated with said bearing box and said axle for enabling said bearing box to carry said axle and said press screw with it in its backward and forward movements.

HERMAN ZWART. 

